 We are going to start with a liquid and change it to a solid.  What is this phase change called?  What needs to happen to the energy level in our liquid to make it become a solid?  How are we going to change the energy level?

 You will be working in groups of 4  2 members of your group will get the ice cream mixture ready.  The other 2 members will get the ice and salt mixture ready.

 Supplies are on the front table  Place in 1 quart size bag  2 cups Milk  1/3 cup sugar  1 tsp. Vanilla

 Supplies are in the back  Fill a gallon size bag  Half full with ice  Add ½ cup rock salt

 Place Masking Tape over the opening of the bag with your ice cream mixture.  This will help to prevent salt water getting into your ice cream.

 Place your ice cream bag into the bag that has your ice/salt mixture.  Try to get the ice to surround your ice cream bag.  Shut the large bag.

 Wrap your bag in 5 or 6 sheets of newspaper.  Newspaper and tape can be found in the back of the class room.

 Use masking tape to secure paper around your bag.  Do not be excessive with your tape.

 Keep your bag in constant motion for 20 minutes.  Shake it  Pass it  Keep it moving, but be careful you don’t want a hole to form in either bag. (Salt tastes bad!)

 After you have kept it moving for 20 minutes it is now time to check and see if your ice cream is done.  It should have become a soft solid.  If it’s done divide it between the members of your group and enjoy. Cups, napkins, and spoons are located at a lab station on the side of the room.

 Put ice/salt mixture in one of the two back sinks.  Throw away plastic bags.  After you have finished eating your ice cream throw away your cups, spoons, ext. and make sure your table is clean.